离子色谱法测定泡菜中亚硝酸盐的测量不确定度评定  

Uncertainty Evaluation of Nitrite Determination in Pickles by Ion Chromatography

作　　者：占永革[1] 黄湘燕 龚剑[1] 

机构地区：[1]广州大学环境检测中心,广东广州510006 [2]中山市供水有限公司水质检测中心,广东中山528403

出　　处：《食品科学》2011年第22期163-170,共8页Food Science

基　　金：国家自然科学基金青年基金项目(40903040)

摘　　要：为探索不同处理方法对化学测量不确定度评估精度的影响,分别用一般的线性拟合法和较严密的非线性拟合法评估校准曲线拟合浓度的不确定度分量,用一般的体胀系数法和较严密的密度修正法评估溶液体积变化的不确定度分量,用近似算式和较严密的算式评估加标回收率的不确定度分量。结果显示:严密法得到的扩展不确定度的精度较一般法高;对于接近符合限的检测结果,严密法可判定亚硝酸盐含量合格,而一般法无法判定。评估者只要遵循检测过程,按实际数据评估,则可获得较高且合理的评估精度。To investigate the influence of data processing on the expanded uncertainty accuracy in the chemical determination of nitrite in pickles,the uncertainty components of calibration curve were fitted with a general linear model and a more rigorous nonlinear model,respectively.Meanwhile,the uncertainty components of solution volume were assessed with a general body expansion coefficient method and a more strict density correction method,respectively.The uncertainty components of spike recovery were evaluated using an approximate formula and a more rigorous formula.The results showed that the expanded uncertainty accuracy obtained from the strict method was higher than that from the general method.For those test results close to the limited boundary,the strict methods,but not the general methods could be used to evaluate the quality of nitrite determination.When the correct testing process is followed,a higher and reasonable evaluation accuracy can be achieved using real data.

关 键 词：不确定度 亚硝酸盐 腌菜 离子色谱 非线性拟合 体积变化 回收率 合格评定 

分 类 号：TB99[一般工业技术—计量学]